1. Field of the Invention:
This invention relates to an image recording apparatus arranged to convert an optical image into an electrical image signal by image pick-up means and to record the signal via a recording head onto a flexible record bearing medium.
2. Description of the Prior Art:
During recent years, there have been disclosed various magnetic recording cameras of the kind arranged to convert an optical image into an electrical image signal by means of an image sensor such as a CCD and to magnetically record the converted image signal on a disc-shaped magnetic recording sheet via a magnetic recording head. In a magnetic recording camera of this kind, contact between the magnetic head and the magnetic sheet plays an important role. The term "contact" as used herein for the purpose of the present invention, includes the case where the magnetic head and the magnetic sheet confront each other across an air flow developed as the magnetic sheet travels. Inadequate contact between the sheet and the head causes a loss called spacing loss. The space loss either hinders recording on the magnetic sheet or makes it impossible to transfer adequate magnetic energy to the magnetic sheet.
The degradation of the contact state is attributable not only to the condition of the magnetic head but also much to the deformation of the magnetic sheet and the vibrations of the sheet which takes place when the sheet rotates. The deformation of the magnetic sheet likewise degrades the contact relation between the magnetic sheet and the magnetic head also during a reproducing operation and thus makes it impossible to obtain sufficient reproduction output. In addition to that trouble, the vibrations of a deformed magnetic sheet during its rotation tends to damage the magnetic head.
With the exception of forced deformation caused by an external force, the deformation of a magnetic sheet mostly takes place when the head and the sheet are left in contact with each other over an excessively long period of time with the sheet not driven. To avoid this trouble, it has been proposed to bring the magnetic head and the magnetic sheet into or out of contact with each other in response to an operation on a lock member for a release or trigger button of the camera. More specifically, either the magnetic head or the magnetic sheet is retracted to bring them out of contact with each other when the release or trigger button is locked and to bring them into contact with each other when the release or trigger button is unlocked. In accordance with this arrangement, however, if the release or trigger button is left in an unlocked state over a long period of time, the magnetic sheet would be likewise deformed. The prior art arrangement is, therefore, not satisfactory.
On the other hand, in the case of a magnetic disc recording and reproducing device employed as an external storage device for a computer or the like, the magnetic head is arranged to be brought into contact with the flexible magnetic disc of the device only at the time of recording or reproduction for the purpose of lengthening the service lives of the magnetic disc and the magnetic head and also for preventing the deformation of the magnetic disc. However, if this arrangement is applied as it is to an electronic camera, it necessitates use of an additional drive source, such as a plunger, for moving the magnetic head or the magnetic sheet into or out of contact with each other. Therefore, such arrangement is also unsatisfactory in terms of electric energy consumption and reduction in size of the camera. Besides, the use of such a discrete drive source complicates sequential exposure control operations.